Sleep Paralysis, Extraordinary Experiences, and Belief in the Supernatural

We investigated sleep paralysis (SP) with an online questionnaire and used a selected sample of subjects who had had at least one SP experience, with a total of 380 subjects. On average, the participants experienced 10–20 SP episodes. We created our own questionnaire on SP experiences by taking items from two already existing questionnaires, the Waterloo Sleep Experience Survey (WSES; Cheyne & Rueffer, 1999) and the Unusual Sleep Experiences Questionnaire (USEQ; Paradis et al., 2009) and adding some items of our own given our emphasis on interpretation, coping strategies, and paranormal aspects of SP. In addition, we have applied three further questionnaires, the Fragebogen zur Phänomenologie außergewöhnlicher Erfahrungen (PAGE-R-II, in press; see Fach et al., 2013, for the first, longer version) to measure extraordinary experiences; a German translation of the Belief in the Supernatural Scale (BitSS; Schofield et al., 2018); and a German translation (Ritz et al., 1993) of the Tellegen Absorption Scale (TAS; Tellegen & Atkinson, 1974) to measure the personality trait absorption. 

We presented first descriptive results of quantitative data with a poster at the 2019 PA convention in Paris (cf. Mayer & Fuhrmann, 2021). One of our research questions concerned the connection between the frequency of SP experiences and extraordinary experiences in general, and belief in the supernatural. The often bizarre and disturbing quality of the experience, the lack of familiar cultural patterns of interpretation in our society, and the accompanying somatic and mental circumstances link SP experiences to the realm of extraordinary experiences (ExEs) and altered states of consciousness (ASC). 

SP is usually experienced as very unpleasant and anxiety-provoking. In addition of being unable to move, many of the concerned have auditive, visual, or tactile perceptions such as hearing voices, seeing strange objects or entities of various kinds, feeling pressure or weight on the chest, being choked, feelings of floating or falling, out-of-body experiences, etc. From the point of view of sleep medicine, the specific quality of such experiences is considered hallucinatory and harmless, and therefore does not require greater attention. However, Belz and Fach (2012, 2015) took a different approach. They included SP as a specific ExE in their model of fundamental categories of exceptional phenomena. They theoretically derived four classes of ExEs, assigned to the four quadrants formed by the dimensions “external–internal” and “coincidence–dissociation.” In their model, SP is placed in the quadrant built by the external and the dissociation poles, i.e., experienced as external and disconnected from normal body function. We used their questionnaire, the PAGE-R-II, to assess the extent to which people with SP have had other extraordinary experiences. We expected positive correlations between the frequency of SP and the experience of “External Phenomena” and “Dissociation Phenomena.” This hypothesis was confirmed regarding the “dissociation” pole but not regarding the “external–internal” dimension. 

Together with some other findings, this led to the assumption that there are two main types of experiencing SP: a “classic” one associated with anxiety and an external attentional focus, and another one with more inward focus, more often associated with positive feelings. We explored this thesis by conducting two factor analyses. With the first, we reduced the 10 items on the list of feelings and emotions experienced during SP to the three emotion factors: a “happiness–curiosity” factor, a “fear–pain” factor, and an “other fears–feelings” factor. In a second step, we computed a factor analysis on the so-called hallucination factors found by Cheyne et al. (1999): the emotion factors, the four subscales of the PAGE, and the TAS. The 3-component-solution suggests two general types of SP experiences as suggested above. However, this hypothesis requires further investigations. 

Many Western scientists consider SP experiences to be one of the sources and causes of human belief in ghosts due to the specific perceptions mentioned above. Based on previous research, we expected a positive correlation between belief in the paranormal and frequency of SP, using a German translation of the BitSS. This hypothesis was not confirmed. The absence of significant correlations between supernatural beliefs and frequency of SP in our study tend not to support the assumption that SP is a major source of human belief in ghosts – at least this is true for our sample coming from a secular Western society.